For Tired, Sore, or Cramping Muscles Dietary Supplement Vegan Gluten Free Non GMO Calmful Muscles was created for tired, sore, or cramping muscles and to promote quick recovery after workouts or exertion. It features relaxing Natural Vitality's Calm, along with L-carnitine, beet root powder, and bromelain, to help the muscles recover quickly. Multi-award-winning Natural Vitality's Calm, developed by Peter Gillham, is the best-selling magnesium supplement in the natural products market.